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Electrically Evoked Assisted Eye-Lid Closure
784
AMERICAN JOURNAL OF OPHTHALMOLOGY
tween the actual and predicted changes in astigmatism created. This study indicates that although corneal wedge resection may play a role in the correction of post operative astigmatism it is still not possi ble to predict with any degree of accuracy the final result of this procedure. Q U A N T I T A T I V E ANALYSIS O F P H A G O C Y T O S I S BY R E T I N A L P I G M E N T EPITHELIUM
T. Rosenstock, N. S. Ranadive, and P. K. Basu We developed a model for quantitative analysis of phagocytosis by the retinal pigment epithelium. Organ culture of bo vine retinal pigment epithelium (as eye cups) was incubated with 1.1-u.m latex particles which had been previously coated with radioactive iodine labelled gammaglobulin. The amount of radioac tivity per eye cup was an accurate indica tion of the amount of phagocytosis that occurred. It was verified by means of electron microscopy that the particles were indeed internalized by the retinal pigment epithelium. Electron micro graphs also indicated that the microvilli were incorporated into the cellular mem brane during phagocytosis. There was a latent period of at least eight hours before any significant uptake of particles oc curred. A slowing of the phagocytic pro cess occurred at about 24 hours. Phagocy tosis was significantly inhibited by iodoacetate (P < .005), colchicine (P < .01), and dibutyryl cGMP (P < .01) each at a concentration of 10~3M. Dibutyryl cAMP at the same concentration did not have any significant effect on phagocyto sis. ELECTRICALLY EVOKED ASSISTED E Y E - L I D CLOSURE
L. Schonberger and J. Hurwitz There is no completely satisfactory treatment of the ocular complications of a
OCTOBER, 1979
facial nerve palsy. We devised an experi mental method of producing eyelid movement in a rabbit with a facial palsy. A facial palsy was obtained by resec tion of the facial nerve in the parotid gland and injection of 95% alcohol with lidocaine (Xylocaine) above the parotid gland. The lead electrode was placed in tramuscularly in the pretarsal muscle and the ground electrode was placed intra muscularly at the orbital rim. The experi mental model was then subsequently subjected to both pulsatile and nonpulsatile stimuli by using a Grass S 88 unit with a constant current unit attachment. We were successful in achieving a sat isfactory eyelid movement and complete eyelid closure in a rabbit with a facial nerve palsy. The minimal current re quired for full eyelid closure could be achieved without discomfort in the fully awake rabbit. DIFFERENTIATION O F POSTGANGLIONIC F R O M P R E G A N G L I O N I C L E S I O N S IN RABBITS W I T H SURGICALLY PRODUCED H O R N E R ' S SYNDROME
B. Skarf and J. Czarnecki A lesion anywhere along the sympa thetic pathway from the brain to the eye will result in an ipsilateral Horner's syn drome. Postganglionic lesions, that is, those involving or distal to the superior cervical ganglion, are usually benign. Pre ganglionic lesions, that is, those more proximal to the superior cervical ganglion, are frequently not benign. The hypothesis has been made that hydroxyamphetamine, a sympathimometic drug that re leases noradrenaline at the myoneural junction and dilates the normal pupil, differentiates postganglionic from pre ganglionic lesions in Horner's syndrome. To test this hypothesis experimentally, two groups of rabbits with surgically produced Horner's syndrome were stud ied. One group had postganglionic le sions as a result of excision of the superior
AMERICAN JOURNAL OF OPHTHALMOLOGY
tween the actual and predicted changes in astigmatism created. This study indicates that although corneal wedge resection may play a role in the correction of post operative astigmatism it is still not possi ble to predict with any degree of accuracy the final result of this procedure. Q U A N T I T A T I V E ANALYSIS O F P H A G O C Y T O S I S BY R E T I N A L P I G M E N T EPITHELIUM
T. Rosenstock, N. S. Ranadive, and P. K. Basu We developed a model for quantitative analysis of phagocytosis by the retinal pigment epithelium. Organ culture of bo vine retinal pigment epithelium (as eye cups) was incubated with 1.1-u.m latex particles which had been previously coated with radioactive iodine labelled gammaglobulin. The amount of radioac tivity per eye cup was an accurate indica tion of the amount of phagocytosis that occurred. It was verified by means of electron microscopy that the particles were indeed internalized by the retinal pigment epithelium. Electron micro graphs also indicated that the microvilli were incorporated into the cellular mem brane during phagocytosis. There was a latent period of at least eight hours before any significant uptake of particles oc curred. A slowing of the phagocytic pro cess occurred at about 24 hours. Phagocy tosis was significantly inhibited by iodoacetate (P < .005), colchicine (P < .01), and dibutyryl cGMP (P < .01) each at a concentration of 10~3M. Dibutyryl cAMP at the same concentration did not have any significant effect on phagocyto sis. ELECTRICALLY EVOKED ASSISTED E Y E - L I D CLOSURE
L. Schonberger and J. Hurwitz There is no completely satisfactory treatment of the ocular complications of a
OCTOBER, 1979
facial nerve palsy. We devised an experi mental method of producing eyelid movement in a rabbit with a facial palsy. A facial palsy was obtained by resec tion of the facial nerve in the parotid gland and injection of 95% alcohol with lidocaine (Xylocaine) above the parotid gland. The lead electrode was placed in tramuscularly in the pretarsal muscle and the ground electrode was placed intra muscularly at the orbital rim. The experi mental model was then subsequently subjected to both pulsatile and nonpulsatile stimuli by using a Grass S 88 unit with a constant current unit attachment. We were successful in achieving a sat isfactory eyelid movement and complete eyelid closure in a rabbit with a facial nerve palsy. The minimal current re quired for full eyelid closure could be achieved without discomfort in the fully awake rabbit. DIFFERENTIATION O F POSTGANGLIONIC F R O M P R E G A N G L I O N I C L E S I O N S IN RABBITS W I T H SURGICALLY PRODUCED H O R N E R ' S SYNDROME
B. Skarf and J. Czarnecki A lesion anywhere along the sympa thetic pathway from the brain to the eye will result in an ipsilateral Horner's syn drome. Postganglionic lesions, that is, those involving or distal to the superior cervical ganglion, are usually benign. Pre ganglionic lesions, that is, those more proximal to the superior cervical ganglion, are frequently not benign. The hypothesis has been made that hydroxyamphetamine, a sympathimometic drug that re leases noradrenaline at the myoneural junction and dilates the normal pupil, differentiates postganglionic from pre ganglionic lesions in Horner's syndrome. To test this hypothesis experimentally, two groups of rabbits with surgically produced Horner's syndrome were stud ied. One group had postganglionic le sions as a result of excision of the superior